<template>
  <div :style="{ padding: '0 0 32px 32px' }">
    <h4 :style="{ marginBottom: '20px' }">{{ title }}</h4>
    <v-chart :data="data" :force-fit="true" :height="height" :onClick="handleClick" :scale="scale">
      <v-tooltip/>
      <v-axis/>
      <v-legend/>
      <v-line color="x" position="type*y"/>
      <v-point :shape="'circle'" :size="4" :v-style="style" color="x" position="type*y"/>
    </v-chart>
  </div>
</template>

<script>
import {DataSet} from '@antv/data-set'
import {ChartEventMixins} from './mixins/ChartMixins'

export default {
  name: 'LineChartMultid',
  mixins: [ChartEventMixins],
  props: {
    title: {
      type: String,
      default: ''
    },
    dataSource: {
      type: Array,
      default: () => [
        {type: 'Jan', jeecg: 7.0, jeebt: 3.9},
        {type: 'Feb', jeecg: 6.9, jeebt: 4.2},
        {type: 'Mar', jeecg: 9.5, jeebt: 5.7},
        {type: 'Apr', jeecg: 14.5, jeebt: 8.5},
        {type: 'May', jeecg: 18.4, jeebt: 11.9},
        {type: 'Jun', jeecg: 21.5, jeebt: 15.2},
        {type: 'Jul', jeecg: 25.2, jeebt: 17.0},
        {type: 'Aug', jeecg: 26.5, jeebt: 16.6},
        {type: 'Sep', jeecg: 23.3, jeebt: 14.2},
        {type: 'Oct', jeecg: 18.3, jeebt: 10.3},
        {type: 'Nov', jeecg: 13.9, jeebt: 6.6},
        {type: 'Dec', jeecg: 9.6, jeebt: 4.8}
      ]
    },
    fields: {
      type: Array,
      default: () => ['jeecg', 'jeebt']
    },
    // 别名，需要的格式：[{field:'name',alias:'姓名'}, {field:'sex',alias:'性别'}]
    aliases: {
      type: Array,
      default: () => []
    },
    height: {
      type: Number,
      default: 254
    }
  },
  data() {
    return {
      scale: [{
        type: 'cat',
        dataKey: 'x',
        min: 0,
        max: 1
      }],
      style: {stroke: '#fff', lineWidth: 1}
    }
  },
  computed: {
    data() {
      const dv = new DataSet.View().source(this.dataSource)
      dv.transform({
        type: 'fold',
        fields: this.fields,
        key: 'x',
        value: 'y'
      })
      let rows = dv.rows
      // 替换别名
      rows.forEach(row => {
        for (let item of this.aliases) {
          if (item.field === row.x) {
            row.x = item.alias
            break
          }
        }
      })
      return rows
    }
  }
}
</script>

<style scoped>

</style>